package com.yunbiji.demo.interceptor;

import lombok.extern.slf4j.Slf4j;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 * 登陆检查
 * 1.配置好拦截器拦截那些请求
 * 2.拦截器在容器中
 *
 */
@Slf4j
public class LoginInterceptor implements HandlerInterceptor {
    /**
     * 之前
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        String resquestUrl = request.getRequestURI();
        log.info("preHandle拦截的路径是{}",resquestUrl);
        //登陆检查
        HttpSession session = request.getSession();
        Object loginUser = session.getAttribute("userId");

        if (loginUser != null){
            //放行
            return true;
        }

        //拦截住
        session.setAttribute("msg","please login before this!");
        request.getRequestDispatcher("/").forward(request,response);
        return false;


    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        log.info("postHandle执行{}",modelAndView);
    }

    /**
     * 之后
     * @param request
     * @param response
     * @param handler
     * @param ex
     * @throws Exception
     */
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        log.info("afterCompletion执行异常{}",ex);
    }
}
